olygt

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I know it's been mentioned how important it is to just understand the mechanisms and not to memorize ..... afterall the MCAT tests for understanding and not memorizing. I'm having a huge problem trying to figure out the orgo. mechanisms conceptually. Everytime I have one mechanism down, just my memorizing the steps, I forgot the other ten reactions I learned before that. For instance, the transesterification mechanism has about eight steps. All I see are arrows, electrons coming in/out and I have no understanding of why. So my question is, wouldn't it be easier to just memorize how the end product should look given a certain reaction because I know there isn't enough time on the MCAT to be tracing electrons.
 

sicboy188

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using route memorization this way will not help you in orgo (and often is a detrement). What helped me is drawing all the mechanism in their simpliest and most general form (using R groups as substituents). I would just draw them over and over. As you draw them, you start to notice patterns that are applicable to all mechanism.

this is the single most important thing that helped me do well in the course. there are only a few rules in orgo. the rest is just application to specific (and often squirly) circumstances. why.. cause orgo profs hate pre-meds.
 

DoctorDreamer

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I know it's been mentioned how important it is to just understand the mechanisms and not to memorize ..... afterall the MCAT tests for understanding and not memorizing. I'm having a huge problem trying to figure out the orgo. mechanisms conceptually. Everytime I have one mechanism down, just my memorizing the steps, I forgot the other ten reactions I learned before that. For instance, the transesterification mechanism has about eight steps. All I see are arrows, electrons coming in/out and I have no understanding of why. So my question is, wouldn't it be easier to just memorize how the end product should look given a certain reaction because I know there isn't enough time on the MCAT to be tracing electrons.
Orgo is like the same 3 things happening over and over again, just with different combinations and reagents.

Just think it through. If you have a molecule with one R group, is there another R group present that might replace it? If so, will it replace it by bumping the other out (inverted shape - SN1) or by the other leaving and then it taking its place (racemic - SN2). If a carbocation intermediate was formed, was kit in its most stable form?

Don't memorize each little step. Just figure out why each reaction works the way it does and get used to reasoning them out. Then, if you lose everything you memorized on test day, you can still reason through most of it.
 

medisforme

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using route memorization this way will not help you in orgo (and often is a detrement). What helped me is drawing all the mechanism in their simpliest and most general form (using R groups as substituents). I would just draw them over and over. As you draw them, you start to notice patterns that are applicable to all mechanism.

this is the single most important thing that helped me do well in the course. there are only a few rules in orgo. the rest is just application to specific (and often squirly) circumstances. why.. cause orgo profs hate pre-meds.
Excellent advice. I did something similar when i took orgo. I took turns drawing out random mechanisms over and over and over until i was sick of them, and then i drew them out some more. for people who find orgo uninteresting (ie. me) this is a very useful way to get a good grade as long as you are willing to study at nauseam (A+, A- for me in orgo 1 and 2 and i hate chemistry more than any other subject.)
 

JA Prufrock

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Understanding the mechanism involves understanding why the electrons go where they are going. For example, you mentioned transesterification. In the acid-catalyzed transesterification, the electrons from the alcohol (a weak nucleophile) attack the carbonyl carbon of the ester because there is a large partial positive charge on that carbon. Do you understand why there is a partial positive charge on the carbon? If not, then you need to read up on some theory before getting into the rxns. Understand the chemistry behind what is happening...memorizing the arrows won't do much good.
 
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olygt

olygt

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Understanding the mechanism involves understanding why the electrons go where they are going. For example, you mentioned transesterification. In the acid-catalyzed transesterification, the electrons from the alcohol (a weak nucleophile) attack the carbonyl carbon of the ester because there is a large partial positive charge on that carbon. Do you understand why there is a partial positive charge on the carbon? If not, then you need to read up on some theory before getting into the rxns. Understand the chemistry behind what is happening...memorizing the arrows won't do much good.

It's because the oxygen is more electronegative than the carbon, so the carbonyl carbon is partial positive, but this still doesn't help me with knowing if something is added to the compound or if the reaction should yield a substitution (e.g. wittig and transesterification are substitution and grignard is addition). The only way I would know this is by associating the reaction names with addition or substitution. Is there a better way?
 

JA Prufrock

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It's because the oxygen is more electronegative than the carbon, so the carbonyl carbon is partial positive, but this still doesn't help me with knowing if something is added to the compound or if the reaction should yield a substitution (e.g. wittig and transesterification are substitution and grignard is addition). The only way I would know this is by associating the reaction names with addition or substitution. Is there a better way?
that's true, you kind of just have to memorize what it's classification is. That involves diagnosing what conditions yield what reactions. Some of it will be more intuitive than others, but as others suggested, the best way to nail this down is work lots of practice problems.
 

GoldShadow

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Organic chemistry is all acids and bases; ie, glorified positives and negatives (charges). Negative likes positive, and positive likes negative.

Once you realize that, it becomes a lot easier to figure out what attacks what and what goes where. I don't try to memorize mechanisms (unless they deviate from the norm). Instead, I try to reason my way through a reaction to figure out the mechanism. I don't memorize reactions either; I reason my way through a mechanism to figure out the products of a reaction.
 

Auron

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Do you guys make note cards? I'm in o-chem 2 right now, and I'm having a hard time..especially with finals next week I'm kinda scared. I'm doing well in all my other classes except this class, damn o-chem....

Can you guys post the study methods you used? and for the final exam? I seem to have trouble putting all the info together...
 

GoldShadow

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I made a note card for every reaction we went through... though many of the reactions near the end of class were repetitive or obvious so I didn't make one for every single one of those.
 

Jules Winnfield

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I know it's been mentioned how important it is to just understand the mechanisms and not to memorize ..... afterall the MCAT tests for understanding and not memorizing. I'm having a huge problem trying to figure out the orgo. mechanisms conceptually. Everytime I have one mechanism down, just my memorizing the steps, I forgot the other ten reactions I learned before that. For instance, the transesterification mechanism has about eight steps. All I see are arrows, electrons coming in/out and I have no understanding of why. So my question is, wouldn't it be easier to just memorize how the end product should look given a certain reaction because I know there isn't enough time on the MCAT to be tracing electrons.

I suggest you try this new thing called studying. Apparently a lot of pre-med students do it and they find that it facilitates a deeper understanding of the material. :)
 

Jules Winnfield

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Do you guys make note cards? I'm in o-chem 2 right now, and I'm having a hard time..especially with finals next week I'm kinda scared. I'm doing well in all my other classes except this class, damn o-chem....

Can you guys post the study methods you used? and for the final exam? I seem to have trouble putting all the info together...

I outlined every chapter and the lecture notes by making studyguides. Then I spent some time figuring out what material would be good to memorize with note cards and memorized those. After all that I just did all of the practice problems from the book, and then did them over and over again until they were like 2nd nature.

Finally for each exam I googled for practice exams that some profs post online. Or find someone who has all of the old exams. Make 10-12 blank copies for each of those and take them as if they were the actual exam. Occaisionally me and some classmates made pretend exams for each other to take, which works really well for multi-step synthesis problems.
 

Auron

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I'm working on a take home quiz right now for o-chem over enolate reactions and I have no idea what to do....wtf..I'm just staring at the page. This class has paralyzed me with fear, and I don't know what to do.
 

mathlete

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Why do people keep insisting on calling it "orgo"?
Lol, exactly. I HATE "orgo". Ochem sounds better. I've heard orgo is an east-coast term and Ochem is used on the West coast.

Flashcards never work for me and I find them leading to memorization more than understanding the concept. I always make a summary sheet with every reaction on it in its simplest form, then review the sheet many many time and understand what makes one reaction different than the rest so I won't confuse them...
 

lilmuck03

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I agree with the flash cards, but only to memorize structures. When I took it, I used a giant white board to diagram reactions over and over again. This helped me put the details together to form a cohesive idea of the reactions.
 

DoctorDreamer

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first, please don't confuse the OP any more than she already is...SN2 reactions proceed with inversion of configuration while SN1 reactions can lead to racemic mixtures due to the formation of an sp2 hybridrized carbocation.
You're right. I spazzed for a minute (confused SN2 with two steps versus two species involved in the rate determining step - OChem was a long time ago). Sorry, OP, although my point was not intended to teach you any ochem, but simply to show you my (apparently flawed, lol) though process in working through problems.
 

DrGregoryHouse

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I know it's been mentioned how important it is to just understand the mechanisms and not to memorize ..... afterall the MCAT tests for understanding and not memorizing. I'm having a huge problem trying to figure out the orgo. mechanisms conceptually. Everytime I have one mechanism down, just my memorizing the steps, I forgot the other ten reactions I learned before that. For instance, the transesterification mechanism has about eight steps. All I see are arrows, electrons coming in/out and I have no understanding of why. So my question is, wouldn't it be easier to just memorize how the end product should look given a certain reaction because I know there isn't enough time on the MCAT to be tracing electrons.
Medical school is all memorization. Get used to it.
 

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Most of the patterns are highlighted/emphasized in the Organic Chemistry as a Second Language book. I highly recommend these books as they make these ideas clearer. I've also heard good things about the Arrow Pushers (or something like that) books.
 

175961

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I'd say orgo rolls off the tongue a little easier
maybe so....but to the unsuspecting it may sound like youre taking a class on kinky sex and how it applies to relationships

"oh i'm taking orgo chemistry"
"yeah i'm in this fairly hard class, orgo"

hmmmmmm, I think I'll stick with ochem
 

Character

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i understand what you are going through. i finished practice test 4r the other day. got 100% of regular bio correct, but 70% of the ochem wrong. all of my wrong aNSwers in the bio section were ochem questions..
 

GoldShadow

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maybe so....but to the unsuspecting it may sound like youre taking a class on kinky sex and how it applies to relationships

"oh i'm taking orgo chemistry"
"yeah i'm in this fairly hard class, orgo"

hmmmmmm, I think I'll stick with ochem
Pfff, "OChem" is for *******. "Orgo" is what real men take. :thumbup:
 

scrubsaresexy

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Lol, exactly. I HATE "orgo". Ochem sounds better. I've heard orgo is an east-coast term and Ochem is used on the West coast.
quote]

I'll second that. I live on the east coast, and I've never heard anyone say ochem.

And OP...I feel your pain. I just don't get this s***.
 

Character

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Lol, exactly. I HATE "orgo". Ochem sounds better. I've heard orgo is an east-coast term and Ochem is used on the West coast.
quote]

I'll second that. I live on the east coast, and I've never heard anyone say ochem.

And OP...I feel your pain. I just don't get this s***.
i think you both are *******...:D
 

DoctorRx1986

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I recommend the textbook, "Organic Chemistry 1st edition" by Janice Gorzysnki Smith. I used it extensively for first semester organic chemistry before changing to another book (different professor) for organic 2. By far, this book is one of the best I have ever seen...the author goes over each and every mechanism in the most exquisite detail and explains the theory of why each reaction is proceeding as it is. The illustrations and real-life examples to support the subject matter are outstanding. I finished organic chemistry in December and decided to keep my textbook for love of the subject and sometimes still skim through the book because of the sheer pleasure I get from reading how crystal clear the author explains the material. Plus, the book is relatively thin in comparison to larger organic chem textbooks, most of which are 1,500 pages or so. A new edition, the 2nd, came out last year.
 

nu2004

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I know it's been mentioned how important it is to just understand the mechanisms and not to memorize ..... afterall the MCAT tests for understanding and not memorizing. I'm having a huge problem trying to figure out the orgo. mechanisms conceptually. Everytime I have one mechanism down, just my memorizing the steps, I forgot the other ten reactions I learned before that. For instance, the transesterification mechanism has about eight steps. All I see are arrows, electrons coming in/out and I have no understanding of why. So my question is, wouldn't it be easier to just memorize how the end product should look given a certain reaction because I know there isn't enough time on the MCAT to be tracing electrons.
you need to sit down with someone who REALLY knows their stuff (like maybe a chem grad student) and just take some time to understand why the various steps happen. i thought that the transesterification mechanism was one of the easier mechanisms, honestly.

the problems with the approach you mentioned (memorizing end product) are: 1) there is frequently more than one possible product, and 2) the MCAT might give you several similar structures from which to choose, so you have to be able to understand which one is favored from the given conditions.

orgo sucks, but a lot of the people teaching it aren't that great at presenting it in a format that is universally understandable (if such a thing exists). find a paid tutor that fits your learning style and you'll be much better off.
 

Dead

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I second the recommendation for the <i>Second Language</i> books. I bombed my first ochem exam and bought and studied from that book. Next exam 98% and I finished that quarter with a 3.9 in ochem. Second quarter I got a 4.0. I'm in the third quarter now and we'll see how I do, but I found second quarter and this quarter so much easier because I had learned to study from the perspective offered in the <i>Second Language</i> series. It breaks everything down in a much simpler way and helps you see the important patterns and steps so you don't have to memorize.
 

redlight

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I second the recommendation for the <i>Second Language</i> books. I bombed my first ochem exam and bought and studied from that book. Next exam 98% and I finished that quarter with a 3.9 in ochem. Second quarter I got a 4.0. I'm in the third quarter now and we'll see how I do, but I found second quarter and this quarter so much easier because I had learned to study from the perspective offered in the <i>Second Language</i> series. It breaks everything down in a much simpler way and helps you see the important patterns and steps so you don't have to memorize.
a 3.9 in 1 class??
what kind of university do you go to..?
or do you mean a 3.9 overall quarter gpa? thats kinda irrelevant..
 
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olygt

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Most of the patterns are highlighted/emphasized in the Organic Chemistry as a Second Language book. I highly recommend these books as they make these ideas clearer. I've also heard good things about the Arrow Pushers (or something like that) books.
Do you have a link of the second language books you are talking about. I looked it up on amazon and it looks like there are different editions. Which one would you recommend for preparation for the MCAT? Thanks for the help :D
 

redlight

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Caesar

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Organic chemistry is all acids and bases; ie, glorified positives and negatives (charges). Negative likes positive, and positive likes negative.

Once you realize that, it becomes a lot easier to figure out what attacks what and what goes where. I don't try to memorize mechanisms (unless they deviate from the norm). Instead, I try to reason my way through a reaction to figure out the mechanism. I don't memorize reactions either; I reason my way through a mechanism to figure out the products of a reaction.
That is the real secret to Organic. It's simple one you understand that. Then you add that a couple things reduce, a couple oxidize, and a few minor things here and there, but somewhere in the mechanism there is probably some sort of positive and some sort of negative, knowing resonance helps alot.
 

olemissbabydoc

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the name of that second book is "Pushing Electrons" and I highly recommend it. saved my a in organic.
 

Dead

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a 3.9 in 1 class??
what kind of university do you go to..?
or do you mean a 3.9 overall quarter gpa? thats kinda irrelevant..
The 3.9 was for the ochem class alone, the 4.0 for the second quarter of ochem. Those weren't my quarterly GPA's. My quarterly GPA's were a little lower due to other less important classes (Women's Lit, :sleep:). I do credit using the Second Language books for getting me on the right track.
 

JA Prufrock

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For all those recommending books like 'pushing electrons' and 'second language,' what went wrong with your textbooks? My textbook (Wade) has been a very good friend over the past year.
 

Cardiac

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DO: Read your textbook, take practice tests, do all your homework problems, find a friend who's dumber than you and teach them

DON'T: Make notecards, memorize anything (know how to work/derive it), take biological philosophy (ever!)

And no, chem majors still call it orgo. Orgo, Orgo, Orgo.
 

Dazedinvt

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Orgo sounds a little dirty. Therefore I prefer it to Ochem. I love enolates..... because I'm a nerd.